Most psychiatric disorders are polygenic. In addition, each gene involved in particular disorder accounts for a small portion of the variance of a particular behavioural variable. Thus the identification of genes involved in polygenic disorders of this kind and, vice versa, the diagnosis of a psychiatric disorder in a person by genetic means seems to be a most difficult task. Thus clinical diagnoses up to now have to be based on clinical observations which are, of course, quite subjective. The fact that certain psychiatric disorders such as human bipolar affective disorder (BAD) have been demonstrated to be associated with particular genes such as the fsh 16 gene (U.S. Pat. No. 5,914,394) has not substantially affected this situation.
Persons who suffer from psychological disorders often differ in their movement patterns from persons without these disorders, and also among themselves due to the nature of the respective disorder. The movement patterns of persons can be registered by various means, including actigraphs. U.S. Pat. No. 6,241,686 describes a system and a method for predicting human cognitive performance based on data recorded by an actigraph. The method calculates a numerical estimate of cognitive performance for an individual as a continuous function of time. By attributing particular movement patterns to particular psychological disorders it is possible, in principle, to identify or at least make probable the existence of a particular psychological disorder or group of psychological disorders in a person. This attribution does however not have been solved in a convenient manner up to now. The present invention seeks to remedy this deficiency.